Conventional fixed winged aircraft are provided with a variety of aerodynamic control devices which include, for example, flaps, elevators, ailerons, trim tabs, and rudders. These control devices cooperatively operate to increase or decease lift over a given localized aerodynamic control surface for achieving pitch, yaw and roll control of the aircraft. Such control devices are used in both traditional winged and modern stealthy aircraft designs.
These control devices are typically rigid structures which are integrated into the edges of the wings or body (i.e., aerodynamic lifting surfaces) of the aircraft. The control devices are configured to deflect or rotate about an axis of rotation in a hinge-like fashion with respect to the attached aerodynamic lifting surfaces. Traditionally, these conventional control devices are actuated by the application of torque about an axis which is parallel to the trailing edge of the device. As such, the torque or power requirement of such devices is directly proportional to impinging air loads as the control device is rotated into an oncoming airflow. Thus, the greater the desired control device deflection, the greater the torque required to cause and maintain such deflection.
In addition, these conventional control devices are generally rigid structures which maintain their shape while being deflected or rotated about an axis which is generally parallel to the wing trailing edge. As such, gaps or abrupt contour changes occur at the lateral hinge line area of these conventional control devices. Further, as the control devices are rotated, chordwise gaps are formed between the edges of the hinged control devices and the adjacent fixed portions of the wing assembly.
It is contemplated that gaps, abrupt changes, or contour discontinuities occurring between the aerodynamic lifting surface and the attached control device are especially undesirable because they tend to increase aerodynamic drag and lessen the aerodynamic effectiveness of the control surface due to "leakage" at the end portions of the control device.
It is therefore evident that there exists a need in the art for an improved control device system which has a mitigated torque power requirement and mitigates the formation of gaps and abrupt surface contour changes occurring between an aerodynamic lifting surface and an attached control device.